Where do implementations sit against each other on two comparable dimensions?

Needs two normalised, comparable numeric dimensions. The corpus has none above E2 — plotting vendor claims against each other would give a chart the evidence cannot support.

This view is declared in the surface registry and is deliberately not built yet. It is listed rather than hidden so the gap stays visible and measurable — when the evidence above supports it, it becomes buildable, and until then a chart here would assert more than the corpus knows.